mudchute, what are the blue capacitors in the left oto the POT? BTW, I am using ALPS 50k POT, although it is less suitable for wiring rather PCB mounting, it works OK. I am looking now for some wiring-option POTs

In the end, I bought the bare board but using board specific jacks from another seller. Total was about £25 which, although a bit pricey is a simple, neat and tidy solution. I'll report back once it arrives.

A 50k pot will work fine. 100k is also fine. The amp doesn't really care that much. The source driving the amp might. I usually go for a higher value so that I have more flexibility in how I drive the amp. I usually omit the pot entirely, but I did include some on my SSE.